ZA200104870B

ZA200104870B - Halogenated hydrocarbon refrigerant compositions containing hydrocarbon oil-return agents.

Info

Publication number: ZA200104870B
Application number: ZA200104870A
Authority: ZA
Inventors: Donald Bernard Bivens; Barbara Haviland Minor; Hans O Spauschus
Original assignee: Du Pont
Priority date: 1999-01-15
Filing date: 2001-06-14
Publication date: 2002-06-14

Description

TITLE

HALOGENATED HYDROCARBON REFRIGERANT COMPOSITIONS

CONTAINING HYDROCARBON OIL-RETURN AGENTS

FIELD OF THE INVENTION

The present invention relates to refrigerant compositions containing hydrocarbon oil-return agents which solubilize mineral and synthetic oil lubricants with halogenated hydrocarbon refrigerants, thereby permitting efficient return of lubricants from non-compressor zones back to a compressor zone in a refrigeration system.

BACKGROUND

Mineral oils and alkylbenzenes have been conventionally used as lubricants in chloroflucrocarbon-based (CFC) refrigeration systems. However, the lack of solubility of these lubricants in the replacement, non-ozone depleting, hydrofluorocarbon (HFC) refrigerants has precluded their use and necessitated development and use of alternative lubricants for HFC refrigeration systems based on polyalkylene glycols (PAGs) and polyol esters (POEs). While the PAGs and

POEs are suitable lubricants for HFC-based refrigeration systems, they are extremely hygroscopic and can absorb several thousand ppm (parts per million) of water on exposure to moist air. This absorbed moisture leads to problems in the refrigeration system, such as formation of acids which resultant in corrosion of the refrigeration system and formation of intractable sludges. In contrast, mineral oils and alkylbenzenes are much less hygroscopic and have low solubility, less than 100 ppm, for water. Additionally, PAG and POE lubricants are considerably more expensive than the hydrocarbon lubricants, typically on the order of three to six times more expensive. As a consequence, there is a need and an opportunity to resolve this solubility problem so that the refrigeration industry may utilize mineral oil and alkylbenzene lubricants with HFC-based refrigerants.

Hydrochlorofluorocarbon (HCFC) refrigerants are also replacing

CFCs, and in instances as mixtures with HFCs. These HCFC-based refrigerant mixtures are less soluble than CFCs in conventional refrigeration lubricants such as mineral oil. A lubricant change from mineral oil to alkylbenzene is often required when the HCFCs or HCFC/HFC mixtures are used to replace pure CFC- based refrigerants, resulting in more expense to the refrigeration industry.

Consequently, there is a need and opportunity to resolve this low solubility

’ problem so that the refrigeration industry may utilize HCFC and HCFC/HFC- based refrigerants with mineral oil lubricants. :

For the foregoing reasons there is a need in the refrigeration industry for providing oil-return agents that create a solution of lubricant oil (dispersed phase) in a HFC- and/or HCFC-based refrigerant (continuous phase), which permits improved lubricant oil transport through a refrigeration system and lubricant oil return back to the refrigeration system compressor from other : refrigeration system zones.

SUMMARY

The present invention is directed to a refrigerant composition that satisfies the aforesaid need. The refrigerant composition comprises:(a) a halogenated hydrocarbon containing at least one carbon atom and one fluorine atom; (b) an oil selected from the group consisting of mineral oils and synthetic oils; and (c) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms.

The present invention also relates to a refrigerant composition, comprising: (a) a halogenated hydrocarbon containing at least one carbon atom and one fluorine atom; and (b) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms.

The present invention further relates to a lubricant composition for use with a halogenated hydrocarbon refrigerant in compression refrigeration apparatus, comprising: (a) an oil selected from the group consisting of mineral oils and synthetic oils; and (b) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms.

Additionally, the present invention pertains to a process for returning oil from a non-compressor zone to a compressor zone in a compression refrigeration system comprising: (a) contacting an oil, selected from the group 3¢ consisting of mineral oils and synthetic oils, in the non-compressor zone with a halogenated hydrocarbon, containing at least one carbon atom and one fluorine atom, in the presence of a hydrocarbon oil-return agent, containing from six to sixteen carbon atoms, to form a solution comprising oil, halogenated hydrocarbon, and hydrocarbon oil-return agent; and (b) transferring the solution from the non- compressor zone to the compressor zone of the refrigeration system.

L WO 00/42118 PCT/USS9/15935

DETAILED DESCRIPTION

The present invention relates to refrigerant compositions comprising; (a) a halogenated hydrocarbon containing at ieast one carbon atom and one fluorine atom; (b) an oil selected from the group consisting of mineral oils and synthetic oils; and (c) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms, wherein said hydrocarbon oil-return agent forms a solution of said halogenated hydrocarbon and said oil.

The present invention further relates to compositions comprising: (a) a halogenated hydrocarbon containing at least one carbon atom and one fluorine atom; and (b) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms, wherein said hydrocarbon oil-return agent forms a solution of said halogenated hydrocarbon with an oil selected from the group consisting of mineral! oils and synthetic oils.

The present invention further relates to lubricant compositions for use with halogenated hydrocarbon refrigerants in compression refrigeration apparatus, comprising: (a) an oil selected from the group consisting of mineral oils and synthetic oils; and (b) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms, wherein said oil-return agent forms a solution of said oil : 20 with halogenated hydrocarbon refrigerant.

The present invention further relates to a process for returning oil } from a non-compressor zone to a compressor zone in a compression refrigeration system comprising: (a) contacting an oil, selected from the group consisting of mineral oils and synthetic oils, in the non-compressor zone with a halogenated hydrocarbon, containing at least one carbon atom and one fluorine atom, in the presence of a hydrocarbon oil-return agent, containing from six to sixteen carbon atoms, to form a solution comprising oil, halogenated hydrocarbon, and hydrocarbon oil-return agent; and (b) transferring the solution from the non- compressor zone to the compressor zone of the refrigeration system.

Halogenated hydrocarbons of the present invention contain at least one carbon atom and one fluorine atom. Of particular utility are halogenated hydrocarbons having 1-6 carbon atoms containing at least one fluorine atom, optionally containing chlorine and oxygen atoms, and having a normal boiling point of from -30°C to 86°C. By normal boiling point is meant the temperature at which a liquid composition's vapor pressure is equal to one atmosphere. These halogenated hydrocarbons may be represented by the general formula

CoFawi2.xyHxClyO,, wherein w is 1-6, x is 1-9, y is 0-3, and z is 0-2. Preferred of the halogenated hydrocarbons are those in which w is 1-6, x is 1-5, y is 0-1, and z

’ is 0-1. Such halogenated hydrocarbons are commercial products available from a ~ number of sources such as E. I. du Pont de Nemours & Co., Fluoroproducts,

Wilmington, DE, 19898, USA, or are available from custom synthesis companies such as PCR Inc., P.O. Box 1466, Gainesville, Florida, 32602, USA, and additionally by synthetic processes disclosed in art such as The Journal of

Fluorine Chemistry, or Chemistry of Organic Fluorine Compounds, edited by

Milos Hudlicky, published by The MacMillan Company, New York, N.Y., 1962.

Examples of the halogenated hydrocarbons are: CCI,F, (CF C-12), CHCLF (HCFC-21), CHCIF; (HCFC-22), CHF; (HFC-23), CH,CIF (HCFC-31), CH,F, (HFC-32), CH;F (HFC-41), CF;CF; (FC-116), CHCLCF3 (HCFC-123),

CHCIFCCIF, (HCFC-123a), CHCIFCF; (HCFC-124), CHF,CCIF, (HCFC-124a),

CHF,CF; (HFC-125), CH.CICF; (HCFC-133a), CHF,CHF, (HF C-134),

CH.FCF; (HFC-134a), CCIF,CH; (HCFC-142b), CHF,CH,F (HFC-143),

CF3CH, (HFC-143a), CHCIFCH; (HCFC-151a), CHF,CH, (HFC-1523),

CHF2CCl,CF3 (HCFC-225aa), CHCIFCCIFCF; (HCFC-225ba), CHF,CCIFCCIF, (HCFC-225bb), CHCL,CF,CF; (HCFC-225ca), CHCIFCF,CCIF, (HCFC-225c¢b),

CHF,CF,CCLF (HCFC-225cc), CCIF,CHCICF; (HCFC-225da),

CCIF,CHFCCIF, (HCFC-225ea), CFsCHFCCI,F (HCFC-225eb), CHF,CCIFCF; - (HCFC-226ba), CHCIFCF,CF3 (HCFC-226ca), CHF,CF,CCIF, (HCFC-226¢b),

CFsCHCICF; (HCFC-226da), CCIF,CHFCF; (HCFC-226e2), CHF,CF,CF; (HFC-227ca), CFsCFHCF; (HFC-227ea), CHF,CCIFCHF, (HCFC-23 Sba),

CH,FCCIFCF3 (HCFC-235bb), CHCIFCF,CHF, (HCFC-23 Sca), CHyCICF,CF; - (HCFC-235cb), CH,FCF,CCIF, (HCFC-235cc), CHF,CHCICF; (HCFC-23 5da),

CHCIFCHFCF; (HCFC-23 5ea), CHF ,CHFCCIF, (HCFC-23 Seb), CCIF,CH,CF; (HCFC-235fa), CHF,CF,CHF, (HFC-236ca), CH,FCF,CF; (HFC-236¢b),

CHF,CHF CF3 (HFC-236ea), CF3CH,CF; (HFC-236fa), CH,FCF,CHF, (HFC- 245ca), CH;CF,CF; (HF C-245¢cb), CHF,CHFCHF, (HFC-245ea), CH,FCHFCF; (HFC-245eb), CHF>CH,CF3 (HFC-245fa), CH,FCF,CH,F (HF C-254ca),

CH;CF,CHF, (HFC-254cb), CH,FCHFCHF, (HFC-254ea), CH;CHFCF; (HFC- 254eb), CHF,CH,CHF, (HFC-254fa), CH,FCH,CF; (HFC-254fb), CH3CF,CH; (HFC-272ca), CH;CHFCH,F (HFC-272ea), CH;FCH,CH,F (HFC-272fa),

CH;CH,CF,H (HFC-272fb), CHyCHFCH; (HFC-281ea), CH;CH,CH,F (HFC- 281fa), CF;CF,CF,CF,H (HFC-329p), CF3;CF,CFHCF; (HFC-329me),

CF5CF,CF,CFH; (HFC-338q), CF3CF,CH,CF; (HFC-338mf), CF;CF,CFHCF,H (HFC-338pe), CF3sCFHCF,CF,H (HFC-338pce), CHF,CF,CF,CF,H (HF C- —338pcc), CF;CFHCFHCF; (HF C-338mee), CF1€F;CFCRCF HH (HFC42<1 1p). —

CF5CF,CFHCF,CF; (HFC-42-11mce), CF3CF,CF,CFHCF; (HFC-42-11me),

CF;CF,CH,CF;CF; (HF C-43-10mcf), CF;CF,CF,CH,CF; (HFC-43-10mf),

3 ) WO 00/42118 PCT/US99/15935 .

CF5CF2CF,CF,CFH; (HF C-43-10q), CF;CF,CF,CFHCF,H (HFC-43-10pe),

CF3CF,CFHCF,CF,H (HFC-43-10pce), CFsCHFCHFCF,CF; (HFC-43-10mee),

CF;HCF;CF,CF,CF,H (HFC-43-10pccc), CF3CFHCF,CF,CF,H (HFC-43- 10pcce), CF3;CFHCF,CFHCF; (HF C-43-10mece), CF3CF,CF,CF,CF,CF,H (HFC-52-13p), C4FsOCHs3, and C4FsOC,Hs. Preferred of the halogenated hydrocarbons are: CHCIF; (HCFC-22), CHF; (HFC-23), CHF, (HFC-32),

CHCIFCF; (HCFC-124), CHF,CF; (HFC-125), CHF,CHF, (HFC-134), CH,FCF; (HFC-134a), CF;CH; (HF C-143a), CHF,CH; (HFC-152a), CHF,CF,CF; (HF C- 227ca), CF:CFHCF; (HFC-227ea), CF3CH,CF; (HFC-236fa), CHF,CH,CF; (HFC-245fa), CHF,CF,CF,CF.H (HFC-338pcc), CFsaCHFCHFCF,CFs (HFC-43- 10mee), and azeotropic and azeotrope-like halogenated hydrocarbon compositions such as: HCFC-22/HFC-152a/HCFC-124 (R-401A, R-401B, R-401C), HFC- 125/HFC-1432/HFC-134a (R-404A), HFC-32/HFC-125/HFC-134a (R-407A, R- 4078, R-407C), HCFC-22/HFC-143a/HFC-125 (R-408A), HCFC-22/HCFC- 124/HCFC-142b (R-409A), HFC-32/HFC-125 (R-410A), and HFC-125/HFC- 143a (R-507).

The halogenated hydrocarbons of the present invention may further comprise up to 10 weight percent of at least one Cs to Cs hydrocarbon, e.g., propane, propylene, cyclopropane, n-butane, i-butane, and n-pentane. Examples ) 20 of halogenated hydrocarbons containing such C; to Cs hydrocarbons are azeotrape-like compositions of HCFC-22/HFC-125/propane (R-402A, R-402RB) . and HCFC-22/octafluoropropane/propane (R-403A, R-403B).

Oils of the present invention are oils conventionally employed as lubricants in refrigeration apparatus with CFC-based refrigerants. Such oils and their properties are discussed in the 1990 ASHRAE Handbook, Refrigeration

Systems and Applications, chapter 8, titled "Lubricants in Refrigeration Systems", - pages 8.1-8.21. Oils of the present invention comprise the family of compounds commonly known in this field as mineral oils. Mineral oils comprise paraffins (straight-chain and branched-carbon-chain, saturated hydrocarbons), naphthenes (cycloparaffins), aromatics (unsaturated, cyclic hydrocarbons containing one or more rings characterized by alternating double bonds), and nonhydrocarbons (molecules containing atoms such as sulfur, nitrogen, or oxygen in addition to carbon and hydrogen). Oils of the present invention further comprise the family of compounds commonly known in this field as synthetic oils. Synthetic oils comprise alkylaryls (such as linear and branched-alky!-chain alkylbenzenes), synthetic paraffins, and polyalphaolefins. Examples of commercially available lubricant oils of the present invention are Suniso® 3GS, Sontex® 372LT, and

) Calumet® RO-30 (all previous three being naphthenes), Zerol® 150 (an alkylbenzene), and "BVM 100 N" (a paraffin).

The hydrocarbon oil-return agents of the present invention are employed in an effective amount in the present inventive compositions such that a solution of halogenated hydrocarbon and lubricating oil is formed. By “solution” is meant that halogenated hydrocarbon and oil become more miscible in the presence of hydrocarbon oil-return agents such that oil is returned as a homogenous solution with halogenated hydrocarbon from non-compressor zones to a compressor zone in a refrigeration system in a quantity, which maintains acceptable compressor lubrication and thus overall refrigeration system operation.

In the present inventive compositions comprising halogenated hydrocarbon containing at least one carbon atom and one fluorine atom, oil selected from the group consisting of mineral oils and synthetic oils, and hydrocarbon oil-return agent, it is preferred that less than about 10 weight percent of the total composition is hydrocarbon oil-return agent. In a more preferred sense, less than abouts weight percent of the total composition (comprising halogenated + hydrocarbon, oil, and hydrocarbon oil-return agent) is hydrocarbon oil-return agent. Hydrocarbon oil-return agent concentrations greater than about 10 weight percent of the total composition are typically not needed to obtain adequate oil return and have been observed to negatively influence the viscosity of the lubricating oil leading to inadequate lubrication and stress on, or mechanical failure of, the refrigeration apparatus. Higher oil-return agent concentrations than : about 10 weight percent of the total composition have also been observed to negatively influence the capacity and performance of a refrigerant composition.

An effective amount of hydrocarbon oil-return agent in the present inventive compositions leads to halogenated hydrocarbon and oil becoming miscibilized to the extent that adequate return of oil in a compression refrigeration system from non-compressor (e.g., evaporator) to compressor zones is obtained.

Hydrocarbon oil-return agent of the present inventive compositions comprises aliphatic, straight, branched, or cyclic chain hydrocarbons having at least seven carbon atoms and sixteen or less carbon atoms. For example, heptanes, octanes, nonanes, decanes, undecanes, kerosene, and mixtures thereof, and in particular refined kerosene with a sulfur content less than 0.2 weight%.

Preferred of the hydrocarbon oil-return agents are those which are classified as combustible (as opposed to flammable) by ASTM D-93. So-classified combustible hydrocarbons-are preferred as oil-returnagents as theiruse in any quantity will not result in flammability being rendered to a refrigeration composition. A preferred hydrocarbon oil-return agent has from seven to sixteen

Claims

) WHAT IS CLAIMED IS:

1. A refrigerant composition comprising: (a) a halogenated hydrocarbon containing at least one carbon atom and one fluorine atom; (b) an oil selected from the group consisting of mineral oils and synthetic oils; and (c) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms.

2. A refrigerant composition, comprising: (a) a halogenated hydrocarbon containing at least one carbon atom and one fluorine atom; and (b) a hydrocarbon oil-refurn agent containing from ten to sixteen carbon atoms.

3. A lubricant composition for use with a halogenated hydrocarbon refrigerant in compression refrigeration apparatus, comprising: (2) an oil selected from the group consisting of mineral oils and synthetic oils; and (b) a hydrocarbon oil-return agent containing from ten to sixteen carbon atoms. .

4. The composition of claim 1, 2 or 3 wherein said hydrocarbon oil- return agent forms a solution of said halogenated hydrocarbon with an oil selected from the group consisting of mineral oils and synthetic oils.

5. The composition of claim 1 wherein said hydrocarbon oil-return agent comprises less than about 10 weight percent of said refrigerant composition.

6. The composition of claim 1 comprising from about 40 to about 99 weight percent halogenated hydrocarbon, from about 1 to about 60 weight percent oil, and from about 0.01 to about 10 weight percent hydrocarbon oil-return agent.

7. The composition of claims 1 or 2 wherein said halogenated hydrocarbon contains from one to six carbon atoms and at least one atom of fluorine, has a normal boiling point of from about -90°C to about 80°C, and optionally contains chlorine and oxygen atoms.

8. The composition of claim 7, wherein said halogenated hydrocarbon is selected from the group consisting of: CCL,F, (CFC-12), CHCI,F (HCFC-21), CHCIF, (HCFC-22), CHF; (HFC-23), CH,CIF (HCFC-31), CH,F,

(HFC-32), CHsF (HFC-41), CFsCFs (FC-116), CHCL,CF3 (HCFC-123), CHCIFCCIF, (HCFC-123a), CHCIFCF; (HCFC-124), CHF,CCIF, (HCFC-124a), CHF:CF; (HFC-125), CH.CICF; (HCFC-133a), CHF,CHF, (HFC-134), CH,FCF; (HFC-134a), CCIF,CH; (HCFC-142b), CHF,CH,F (HFC-143), CF3CHs (HFC-143a), CHCIFCH; (HCFC-151a), CHF,CH; (HFC-152a),

CHF,CClCF; (HCFC-225aa), CHCIFCCIFCF; (HCFC-225ba), CHF,CCIFCCIF, (HCFC-225bb), CHCL,CF,CF3 (HCFC-225ca), CHCIFCF,CCIF, (HCFC-225¢cb), CHF,CF,CCLF (HCFC-225¢c), CCIF,CHCICF; (HCFC-225da), CCIF,CHFCCIF, (HCFC-225¢ea), CFsCHFCCL,F (HCFC-225¢b), CHF,CCIFCF; (HCFC-226ba), CHCIFCF,CF; (HCFC-226¢4), CHRE,CF,CCIF, (HICFC-226¢b),

CFsCHCICF; (HCFC-226da), CCIF,CHFCF; (HCFC-226ea), CHF,CF,CF; (HFC-227ca), CFsCFHCF; (HFC-227¢a), CHF,CCIFCHF;, (HCFC-235ba), CH,FCCIFCF; (HCFC-235bb), CHCIFCF,CHF, (HCFC-235ca), CH;CICF,CF; (HCFC-235cb), CHFCF,CCIF, (HCFC-235cc), CHF;CHCICF; (HCFC-235da), CHCIFCHFCF; (HCFC-235ea), CHF,CHFCCIF; (HCFC-235¢b), CCIF,CH,CF;

: 20 (HCFC-235fa), CHF,CF,CHF, (HFC-236ca), CH;FCF,CF; (HFC-236cb), CHF,CHFCF; (HFC-236¢a), CF;CH,CF; (HF C-236fa), CH:FCF.CHE, (HFC-

245ca), CH;CF,CF; (HFC-245cb), CHF,CHFCHF, (HFC-245¢1), CH,FCHFCE; (HFC-245¢b), CHF,CH,CF; (HFC-245fa), CH;FCF,CH,F (HFC-254ca), CH,CF,CHF; (HFC-254cb), CH,FCHFCHF, (HFC-254ea), CH; CHFCF3 (HFC-

254eb), CHF,CH,CHF, (HFC-254fa), CH,FCH,CF; (HF C-254fb), CH;CF,CH; (HFC-272ca), CHyCHFCH,F (HIFC-272ea), CH;FCH,CH,F (HFC-2721a), CH>CH,CFH (HF C-272fb), CH;CHFCH; (HFC-281ea), CH;CH,CH,F (HF C- 281fa) , CF;CF,CF,CF;H (HFC-329p), CF3;CF,CFHCF; (HFC-329me), CF3CF,CF,CFH, (HFC-338q), CF3CF,CH,CF; (HFC-338mf), CF;CF,CFHCF,H

(HFC-338pe), CF3CFHCF,CF;H (HFC-338pce), CHF,CF,CF,CF,H (HFC- 338pcc), CFsCFHCFHCF;3 (HF C-338mee), CF3CF,CF,CF,CF,H (HFC-42-11p), CF3CF,CFHCF,CF; (HFC-42-11mce), CF3CF,CF,CFHCF; (HFC-42-11me), CF3CF,CH,CF,CF; ("HF C-43-10mcf), CF;CF,CF,CH,CF; (HF C-43-10mf), CF3;CF,CF,CF,CFH, (HFC-43-10q), CF3CF,CF,CFHCFE,H (HF C-43-10pe),

CFsCF.CFHCF,CF,H (HFC-43-10pce), CF3CHFCHFCF,CF; (HFC-43-10mee), CF,HCF,CF,CF,CF,H (HFC-43-10pccc), CF;CFHCF,CF,CF;H (HFC-43- 10pcce), CF3CFHCF,CFHCF; (HFC-43-10mece), CF3CF,CF,CF,CF,CF,H (HFC-52-13p), C4FsOCHj, and C4FyOC,Hs.

¥

9. The composition of claim 7 further comprising less than about 10 weight percent of at least one Cs to Cs hydrocarbon.

10. The composition of claims 1 or 3 wherein said oil is selected from the group consisting of paraffins, naphthenes, aromatics, alkylaryls, synthetic paraffins, and polyalphaolefins.

11. The composition of claims 1, 2, or 3 wherein said hydrocarbon oil-return agent comprises hydrocarbons containing eleven to thirteen carbon atoms.

12. A process for producing refrigeration comprising evaporating a composition of claims 1 or 2 in the vicinity of a body to be cooled.

13. A process for producing heat comprising condensing a composition of claims lor 2 in the vicinity of a body to be heated.

14. A process for returning oil from a non-compressor zone to a compressor zone in a compression refrigeration system comprising: (a) contacting an oil, selected from the group consisting of mineral oils and synthetic oils, in the non-compressor zone with a halogenated . hydrocarbon, containing at least one carbon atom and one fluorine atom, in the presence of a hydrocarbon oil-return agent , containing from six to sixteen carbon atoms, to form a solution comprising oil, halogenated hydrocarbon, and hydrocarbon oil-return agent; and (b) transferring the solution from the non-compressor zone to the compressor zone of the refrigeration system.

15. The process of claim 14 wherein the hydrocarbon oil-return agent comprises less than about 10 weight percent of the solution comprising halogenated hydrocarbon, oil, and hydrocarbon oil-return agent.

16. The process of claim 14 wherein the solution comprising halogenated hydrocarbon, oil, and hydrocarbon oil-return agent comprises from —4about.40.t0-about-99 weight percent halogenated hydrocarbon, from about 1 to—— about 60 weight percent oil, and from about 0.01 to about 10 weight percent hydrocarbon oil-return agent.

17. The process of claim 14 wherein said halogenated hydrocarbon contains from one to six carbon atoms and at least one atom of fluorine, has a normal boiling point of from about -90°C to about 80°C, and optionally contains chlorine and oxygen atoms.

18. The process of claim 17, wherein said halogenated hydrocarbon is selected from the group consisting of: CCLF; (CFC-12), CHCLF (HCFC-21), CHCIF, (HCFC-22), CHF; (HFC-23), CH,CIF (HCFC-31), CH,F; (HFC-32), CH3F (HFC-41), CF5CF; (FC-116), CHCL,CF3 (HCFC-123), CHCIFCCIF, (HCFC-123a), CHCIFCFs (HCFC-124), CHF,CCIF, (HCFC-124a), CHF,CF; (HFC-125), CH,CICF; (HCFC-133a), CHF,CHF, (HFC-134), CH,FCF; (HFC- 134a), CCIF,CH; (HCFC-142b), CHF,CH,F (HFC-143), CF;CH; (HFC-143a), CHCIFCH; (HCFC-151a), CHF,CH; (HFC-152a), CHF,CCi,CF3 (HCFC-225aa), CHCIFCCIFCF; (HCFC-225ba), CHF,CCIFCCIF, (HCFC-225bb), CHCLCF,CF; (HCFC-225ca), CHCIFCF,CCIF,; (HCFC-225cb), CHF,CF,CCl,F (HCFC- 225cc), CCIF,CHCICF; (HCFC-225da), CCIF,CHFCCIF, (HCFC-225¢a), CF;CHFCCLF (HCFC-225¢b), CHF,CCIFCF3 (HCFC-226ba), CHCIFCF,CF; (HCFC-226ca), CHF,CF,CCIF; (HCFC-226¢b), CF3CHCICF; (HCFC-226da), CCIF,CHFCF; (HCFC-226ea), CHF,CF,CF3 (HIFC-227ca), CF;CFHCE; (HFC- 227ea), CHF,CCIFCHF> (HCFC-235ba), CH;FCCIFCF; (HCFC-235bb), CHCIFCF,CHF; (HCFC-235ca), CH;CICF,CF; (HCFC-235¢cb), CH,FCF,CCIF, (HCFC-235cc), CHF,CHCICF; (HCFC-235da), CHCIFCHF CF; (HCFC-235ea), CHF,CHFCCIF; (HCFC-235¢b), CCIF,CH,CF; (HCFC-235fa), CHF,CF,CHF, (HFC-236ca), CH,FCF,CF3 (HFC-236¢cb), CHF,CHFCF; (HFC-236€a), CFi:CH,CF;3 (HFC-236f3a), CH,FCF,CHF, (HFC-245ca), CH;CF,CF5 (HFC- 245¢b), CHF,CHFCHF, (HFC-245¢ea), CH,FCHFCF; (HFC-245¢eb), CHF,CH,CF; (HFC-245fa), CHFCF,CH,F (HFC-254ca), CH,CF,CHF, (HFC- 254c¢b), CH,FCHFCHF, (HFC-254ea), CH; CHFCF3 (HFC-254¢b), CHF,CH,CHF, (HFC-254fa), CH,FCH,CF3 (HFC-254fb), CH;CF,CH; (HFC- 272ca), CHsCHFCH,F (HF C-272¢a), CHFCH,CH,F (HFC-272fa), CH3CH,CF,H (HFC-272fb), CH;CHFCH;3 (HFC-281ea), CH,CH,CH,F (HFC- 281fa) , CF3CF,CF,CF:H (HFC-329p), CF3CF,CFHCF; (HFC-329me), CF3CF,CF,CFH, (HFC-338q), CF3CF,CH,CF; (HFC-338mf), CF;CF,CFHCF,H (HFC-338pe), CF3:CFHCF,CF,H (HFC-338pce), CHF,CF,CF,CFH (HFC- 338pcc), CFsCFHCFHCF; (HF C-338mee), CF3CF,CF,CF,CF,H (HFC-42-11p), CF,CF,CFHCF,CF3 (HFC-42-11mce), CFsCF,CF,CFHCF; (HFC-42-11me), CF;CF,CH2CF,CF; (HFC-43-10mcf), CE;CFCF,CH,CF3 HF C-43-10mf),

] CF;CF.CF,CF,CFH, (HF C-43-10q), CFsCF,CF,CFHCF,H (HFC-43-10pe), - CFsCF,CFHCF,CF;H (HFC-43-10pce), CF;CHFCHFCF,CF; (HFC-43-10mee), CF,HCF,CF,CF,CF,H (HFC-43-10pccc), CF;CFHCF,CF,CF,H (HFC-43- 10pcce), CFsCFHCF,CFHCF; (HFC-43-10mece), CF3CF,CF,CF,CF,CF,H (HFC-52-13p), C4FsOCHs, and C4FsOC,Hs.

19. The process of claim 17 wherein said halogenated hydrocarbon further comprises less than about 10 weight percent of at least one Cato Cs hydrocarbon.

20. The process of claim 14 wherein the oil is selected from the group consisting of paraffins, naphthenes, aromatics, alkylaryls, synthetic paraffins, and polyalphaolefins.

15.

21. The process of claim 14 wherein said hydrocarbon oil-return agent comprises hydrocarbons containing eleven to thirteen carbon atoms.